The Barn Find Build

[Eric Page]

Have you sighted the trailing edge of the stabilizer to see if it is straight?

I had not, but just did. It's straight as an arrow.

[Eric Page]

I started today by getting the stab trim actuator installed. The bottom end went fine, but I thought at first that the top was going to be a problem. It came from SkyStar with a rod end bearing that has a 1/4" through-hole and uses and bushing to adapt it to an AN3 bolt. The bushing was missing from the hardware I received with the project, but shortly after posting a question about that bushing, I remembered that I had an extra rod end from the three I replaced at the rudder (the other two aren't usable). I replaced the rod end on the actuator with that one, which has a 3/16" through-hole, eliminating the need for a bushing.

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Next I flipped the flaperons over and inspected the other side. One was totally clean of dents and the other had just a few, so I wiped that one with acetone, mixed up 3g of SuperFil and covered those dents.

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I had sprayed primer on the second side of yesterday's antenna ground plane last night, so I scraped away a small ring on the back side for electrical contact and installed the antenna. So, both of those are done.

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Remember how I had to remove the bottom few inches of the fiberglass fairing on the rudder for welding the tail post reinforcement, then reattached the fairing piece and reinforced the cut with thin strips of wood? Yeah... that wasn't a good idea. They're blocking the tips of the rudder stops on both sides so the rudder only has about 10 degrees of movement.

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I think a light touch with the angle grinder should square off those tips and give them clearance, but it sure would have been nice to see that coming and use shorter sticks of wood. And yes, I agree, I need to clean up that SuperFil on the inside of the rudder. I didn't realize that much squeezed through!

Anyway, while the rudder was on-and-off, I got the new rod end bearings set at the right length to set the rudder position. I'll need to reshape the aft end of the vertical stab tip just a bit, as I left it square until I could see how much needed to be removed.

As suggested in a post above, I removed the rod end from the right side horizontal stab brace and shortened it on the disc sander. I also had to shorten the male threads on the end of the brace tube, but I've got a very nice fit now, and there's still lots of thread engagement in the rod end.

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With that sorted out, I got back to the slider blocks. I squeezed them tight against the square tube in the tail, then carefully removed the stab to my work table. I closed them up by what looked like a few thousandths, then drilled through with a #34 and actually hit the hole on the other side of the rectangular tube all four times! With the hardware installed I test fit it and found it too tight, as intended. This allowed me to sand a bit at a time until it slid smoothly into place with zero fore/aft play at the tips of the stab -- a much nicer fit than I had before.

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While I had the horizontal stab on the bench, I began fabricating the cover plates for the brace attachment points. The first builder already installed the brackets they screw into, and they're functional if not pretty, so I didn't try to remove them. I first marked out the cut lines and hole positions, then used the nibbler to cut them out.

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Once drilled, all the holes lined up and it looks like it'll work just great. It'll need a little gentle shaping to sit flush against the aft tube but I'll plan to do that, and make the slot and hole for the brace tube, when I get closer to final assembly.

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I repeated that on the other side with the same result. It's amazing how nicely parts turn out if you think through the process, use the right tools and take your time.

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